The present invention relates to an improvement of a finger peristaltic infusion pump to forcibly flow an infusion mixture such as a drug liquid through a tube in one direction thereof.
There have been devised and demonstrated various types of finger peristaltic infusion pumps of the type in which a liquid such as blood or a drug liquid is pumped through an infusion tube in one direction thereof by peristalsis of the infusion tube. However, in these pumps, a pump mechanism for squeezing or causing peristalsis of an infusion tube is formed integral with the main body of the infusion pump.
When the infusion pumps of the type described above are used in practice, the pump main body and the pump mechanism are frequently immersed with a drug liquid or an infusion mixture leaked from a container disposed above the infusion pump. Especially a drug liquid containing as a major portion glucose tends to increase its concentration due to the evaporation of water, thus resulting in the increase in viscosity. As a result, the operation of the infusion pump is adversely affected. Furthermore, when the infusion pump is not operating, the water is completely evaporated so that glucose remains in the pump, thus preventing the movement or rotation of moving or rotating parts of the infusion pump.
As a result, the object of the infusion pump for pumping an infusion mixture cannot be attained. Whereby there arises the problem that an accident for breaking a power transmission mechanism occurs due to the driving force of a motor.
Furthermore, it is difficult to wash and clean off the leaked infusion mixture so that it is difficult to maintain the infusion pump in a sanitary state.
The conventional pumps cause the wear of a pump mechanism when they have been used for a long time so that they cannot function properly. As a result, the whole infusion pump must be replaced or the pump mechanism must be disassembled and replaced. Therefore, when the time required for maintaining and reparing the broken infusion pumps is taken into consideration, a relatively large number of infusion pumps must be always kept, which is very uneconomical.